Update black, and run auto formatting over the codebase (#9381)

 - Update black version to the latest
 - Run black auto formatting over the codebase
    - Run autoformatting according to [`docs/code_style.md
`](https://github.com/matrix-org/synapse/blob/80d6dc9783aa80886a133756028984dbf8920168/docs/code_style.md)
 - Update `code_style.md` docs around installing black to use the correct version

4 files changed, 26 insertions, 12 deletions

diff --git a/synapse/rest/media/v1/download_resource.py b/synapse/rest/media/v1/download_resource.py
index 3ed219ae43..48f4433155 100644
--- a/synapse/rest/media/v1/download_resource.py
+++ b/synapse/rest/media/v1/download_resource.py
@@ -51,7 +51,8 @@ class DownloadResource(DirectServeJsonResource):
             b" object-src 'self';",
         )
         request.setHeader(
-            b"Referrer-Policy", b"no-referrer",
+            b"Referrer-Policy",
+            b"no-referrer",
         )
         server_name, media_id, name = parse_media_id(request)
         if server_name == self.server_name:
diff --git a/synapse/rest/media/v1/media_repository.py b/synapse/rest/media/v1/media_repository.py
index 635bccf775..a0162d4255 100644
--- a/synapse/rest/media/v1/media_repository.py
+++ b/synapse/rest/media/v1/media_repository.py
@@ -325,7 +325,10 @@ class MediaRepository:
         # Failed to find the file anywhere, lets download it.
 
         try:
-            media_info = await self._download_remote_file(server_name, media_id,)
+            media_info = await self._download_remote_file(
+                server_name,
+                media_id,
+            )
         except SynapseError:
             raise
         except Exception as e:
@@ -351,7 +354,11 @@ class MediaRepository:
         responder = await self.media_storage.fetch_media(file_info)
         return responder, media_info
 
-    async def _download_remote_file(self, server_name: str, media_id: str,) -> dict:
+    async def _download_remote_file(
+        self,
+        server_name: str,
+        media_id: str,
+    ) -> dict:
         """Attempt to download the remote file from the given server name,
         using the given file_id as the local id.
 
@@ -773,7 +780,11 @@ class MediaRepository:
                         )
                     except Exception as e:
                         thumbnail_exists = await self.store.get_remote_media_thumbnail(
-                            server_name, media_id, t_width, t_height, t_type,
+                            server_name,
+                            media_id,
+                            t_width,
+                            t_height,
+                            t_type,
                         )
                         if not thumbnail_exists:
                             raise e
@@ -832,7 +843,10 @@ class MediaRepository:
         return await self._remove_local_media_from_disk([media_id])
 
     async def delete_old_local_media(
-        self, before_ts: int, size_gt: int = 0, keep_profiles: bool = True,
+        self,
+        before_ts: int,
+        size_gt: int = 0,
+        keep_profiles: bool = True,
     ) -> Tuple[List[str], int]:
         """
         Delete local or remote media from this server by size and timestamp. Removes
@@ -849,7 +863,9 @@ class MediaRepository:
             A tuple of (list of deleted media IDs, total deleted media IDs).
         """
         old_media = await self.store.get_local_media_before(
-            before_ts, size_gt, keep_profiles,
+            before_ts,
+            size_gt,
+            keep_profiles,
         )
         return await self._remove_local_media_from_disk(old_media)
 
diff --git a/synapse/rest/media/v1/media_storage.py b/synapse/rest/media/v1/media_storage.py
index aba6d689a8..1057e638be 100644
--- a/synapse/rest/media/v1/media_storage.py
+++ b/synapse/rest/media/v1/media_storage.py
@@ -85,8 +85,7 @@ class MediaStorage:
         return fname
 
     async def write_to_file(self, source: IO, output: IO):
-        """Asynchronously write the `source` to `output`.
-        """
+        """Asynchronously write the `source` to `output`."""
         await defer_to_thread(self.reactor, _write_file_synchronously, source, output)
 
     @contextlib.contextmanager
@@ -342,8 +341,7 @@ class ReadableFileWrapper:
     path = attr.ib(type=str)
 
     async def write_chunks_to(self, callback: Callable[[bytes], None]):
-        """Reads the file in chunks and calls the callback with each chunk.
-        """
+        """Reads the file in chunks and calls the callback with each chunk."""
 
         with open(self.path, "rb") as file:
             while True:
diff --git a/synapse/rest/media/v1/preview_url_resource.py b/synapse/rest/media/v1/preview_url_resource.py
index ae53b1d23f..6104ef4e46 100644
--- a/synapse/rest/media/v1/preview_url_resource.py
+++ b/synapse/rest/media/v1/preview_url_resource.py
@@ -580,8 +580,7 @@ class PreviewUrlResource(DirectServeJsonResource):
         )
 
     async def _expire_url_cache_data(self) -> None:
-        """Clean up expired url cache content, media and thumbnails.
-        """
+        """Clean up expired url cache content, media and thumbnails."""
         # TODO: Delete from backup media store
 
         assert self._worker_run_media_background_jobs